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Wouldn’t it be cool to have crystal-clear cell phone communications with one tenth as many towers? How about being able to toss a handful of pebble-sized devices into the depths of the ocean and record marine activity, sense the presence of undersea earthquakes, locate shipwrecks, and track ships and submarines? Would you like to have a device the size of a cherry tomato that would sit on the dashboard of your car and detect airborne pollutants, sense unusual vibrations in the engine, communicate with satellites for on-board directions, and let you know when you are too close to the car in front of you? One approach to engineering these applications is to create a next generation of electronic devices based on multifunctional materials – that is, create a single device that interacts with its environment mechanically, electronically, optically, and magnetically. The functional integration of different materials at the atomic level presents many challenges to material scientists and engineers. But the potential of these next-generation electronic devices is open to the imagination.

Dr. Ziemer’s research involves engineering surfaces in order to integrate wide bandgap semiconductors with functional and multi-functional oxides, organic molecules, and/or biomaterials. Dr. Ziemer’s group, in the Interface Engineering Laboratory, takes advantage of the ultra-high vacuum environment to study, at the atomic level, the growth and processing of thin films and nanostructures. This “surface engineering” is based on the hypothesis that understanding the atomic-level interactions at a surface will lead to developing processes to create new materials and to effectively interface different materials for new functionalities. The tools used for growth and formation mechanism studies are solid source effusion cells, plasma sources, ion sources, atom sources, and the in-situ analysis tools of reflection high-energy electron diffraction (RHEED), Auger electron spectroscopy (AES), and x-ray photoelectron spectroscopy (XPS). The general approach is shown in Figure 1. Current projects include:

integration of magnetic barium hexaferrite with silicon carbide for self-biasing circulators to enhance the power and portability of microwave frequency communications

integration of multi-functional lead zirconium titanate with silicon carbide and gallium nitride for novel multi-functional devices

integration of live bacteria with gallium nitride for self-repairing, self-calibrating biosensors